My basic rule would be to keep your cards close to your chest. Don't show'em until the last second.
You can caveat that by what kind of commander you have. There's been dudes I worked for who I would trust to tell my plans to, but on the whole, I'd let them keep thinking you're a company man until the very last second that you have.
You never know, you might want to stay in the AF at the last second, and you may have already been passed over for some great opportunity because you were labelled a quitter.